Review Article

Spontaneous Bacterial Peritonitis – Bacteriology, Diagnosis, Treatment, Risk Factors and Prevention

J. B. Dever; M. Y. Sheikh


Aliment Pharmacol Ther. 2015;41(11):1116-1131. 

In This Article


Primary Prophylaxis

Norfloxacin. Spontaneous bacterial peritonitis naïve patients with cirrhosis and low ascitic fluid protein (<1 g/dL) with additional risk factors are candidates to receive long-term norfloxacin therapy for survival benefit[47,126] and to reduce risk of SBP as well as extraperitoneal infections.[127] Norfloxacin has been the most widely studied antibiotic for SBP prevention in a variety of settings including gastrointestinal bleeding,[128] primary SBP prophylaxis[47,127,129,130] and secondary SBP prophylaxis and remains the first-line choice for selective intestinal decontamination. In a double-blind, placebo-controlled trial, patients with low ascitic protein (<1.5 g/dL) and one additional risk factor including advanced cirrhosis (Child score ≥9), serum creatinine 1.2 mg/dL, blood urea nitrogen 25 mg/dL or serum sodium 130 mEq/L who were receiving norfloxacin 400 mg/day had significant survival advantage at 3-month (94% vs. 62%, P = 0.003) and 1-year (60% vs. 48%, P = 0.05) follow-up, as well as decreased risk of hepatorenal syndrome (28% vs. 41%, P = 0.02) and SBP (7% vs. 61%, P < 0.001) at 1-year follow-up.[47]

Ciprofloxacin. The risk of developing an initial episode of community acquired SBP within 1 year is substantially higher (55%) in patients with low ascitic fluid protein (≤1 g/dL) and a bilirubin level greater than 3.2 mg/dL and/or platelet count less than 98 000/mm3 compared to patients without these bilirubin and platelet cut-offs whose risk is approximately 24%.[15] There is one randomised, placebo-controlled trial that examined the role of ciprofloxacin in primary prophylaxis and found that patients with ascitic protein <1.5 g/dL who were receiving oral ciprofloxacin 500 mg/day had a significantly greater chance of survival in 1 year than patients receiving placebo (86% vs. 66%, P < 0.04).[131]

Trimethoprim–Sulfamethoxazole. A randomised controlled trial involving 66 consecutive patients with cirrhosis and ascites at a University-affiliated VA medical centre demonstrated decreased risk of SBP (27% vs. 3%, P = 0.025) and other infections with daily double strength trimethoprim–sulfamethoxazole (Bactrim; Mutual Pharmaceutical Company, Inc., Philadelphia, PA, USA) at 90-day follow-up.[132]

Rifaximin. There is limited and inconsistent data for rifaximin (Xifaxan; Salix Pharmaceuticals, Inc., Raleigh, NC, USA), a non-absorbable antibiotic with broad-spectrum coverage, in primary or secondary SBP prophylaxis.[133,134]

Secondary Prophylaxis

Norfloxacin. Patients with a prior history of SBP are also candidates to receive indefinite antibiotic prophylaxis that is until liver transplantation, resolution of ascites or death. Recurrence of SBP ranges from 43% at 6 months to 74% at 2 years after initial diagnosis.[76] In a double-blind, placebo-controlled study, patients receiving norfloxacin 400 mg/day were less likely to have SBP recurrence at 1-year follow-up (20% vs. 68%, P = 0.0063) compared to patients receiving placebo.[135]

Ciprofloxacin. A meta-analysis reported short-term survival and reduced overall risk of infections with antibiotic prophylaxis when compared to untreated control groups.[126]

Trimethoprim–Sulfamethoxazole. Trimethoprim–sulfamethoxazole demonstrated similar efficacy and adverse effect profile compared to norfloxacin for prevention of SBP recurrence in a retrospective series.[136] Trimethoprim–sulfamethoxazole and norfloxacin for primary and secondary SBP prophylaxis also demonstrated similar and significant cost savings per patient per year.[137]